The present invention relates to systems and methods for enabling medical imaging data registration and more particularly, to systems and methods which enable registration of tissue imaging data for the purposes of enhancing diagnostic resolution.
Medical imaging is routinely used to image the human body or portions thereof for clinical or research purposes.
For over 70 years, medical imaging had almost exclusively depended on conventional film/screen X-ray imaging. However, in the last 40 years, medical imaging has experienced major technological growth which has resulted in the development and commercialization of new imaging technologies. Such technologies, which include X-ray Computed Tomography, Magnetic Resonance Imaging, Digital Subtraction Angiography, ultrasound, thermography and nuclear emission imaging (e.g. PET, SPECT, etc.) are now routinely used in detection and diagnosis of disease.
The availability of such diagnostic technologies provides a physician with a range of diagnostic tools to choose from and also potentially enables correlation (registration) of several different imaging approaches thus greatly enhancing accuracy of diagnosis.
Having a range of diagnostic tools to choose from can potentially enhance the ability of a physician to diagnose a disease, however, it is the correlation of results from several imaging approaches which has the greatest potential in enhancing diagnostic accuracy.
Although a patient can be subjected to multiple imaging approaches (e.g. x-ray and ultrasound), the images obtained are not easily registered or correlated with one another. Differences in scale, position, or in the orientation of the imaging plane are almost inevitable. With certain tissues (e.g. breast) imaging registration is further hampered by deformation of the tissue which can result from the imaging technique (e.g. compression of breast tissue between mammography plates).
The prior art is replete with approaches for enabling registration of medical images, most requiring the use of orientation markers or models which are typically constructed using 3-D imaging approaches (e.g. MRI).
Prior art registration approaches are typically designed for registering imaging data obtained by x-ray, ultrasound or MRI. However, in the case of thermographic imaging, such approaches are incapable of providing an accurate registration since thermographic data is derived from the surface of the imaged body portion rather than the internal tissues.
A thermographic image is typically obtained by collecting from the a body of the subject radiation at any one of several infrared wavelength ranges and analyzing the radiation to provide a two-dimensional temperature map of the surface. The thermographic image can be represented as a visual image with or without corresponding temperature data. The output from infrared cameras used for infrared thermography typically provides an image comprising a plurality of pixel data points, each pixel can provide relative temperature information which is visually displayed, using a color code or grayscale code. This information can be further processed by computer software to generate for example, mean temperature for the image, or a discrete area of the image, by averaging temperature data associated with all the pixels or a sub-collection thereof.
Since shifts in body temperature can indicate the presence of a disorder, (e.g. inflammation caused an increase in temperature), a thermographic image can be used by a physician to determine whether or not a site includes presence of a disorder.
While reducing the present invention to practice, the present inventors have uncovered that surface contour data, especially when combined with thermal imaging data can be used for registration of imaging modalities.